Jo Rae Perkins, who defeated three other candidates in a primary contest to be the Republican candidate, said in a now-deleted video after her victory: “I stand with President Trump. I stand with Q and the team. Thank you Anons, and thank you patriots. And together, we can save our republic.”

The QAnon theory has been embraced by some of the president’s supporters and centers on an alleged government agent named “Q”, whose top security clearance has provided insight into a deep-state conspiracy involving everyone from Hillary Clinton to special counsel Robert Mueller.

It also posits that Donald Trump is leading a behind-the-scenes fight against powerful forces protecting satanic paedophile rings, and that Q leaves clues for followers to decipher on internet forums.

The FBI has warned that the QAnon theory could be a motivator for “domestic extremists” to carry out violence in the US.

In another statement released last night, Perkins tried to downplay her previous support for the conspiracy theory. “To be very clear, I do not believe everything from QAnon and would never describe myself as a follower, but I also do not believe in infringing upon any outlet’s right to discuss news or topics,” she said.

“My slogan, For One Oregon, has nothing to do with conspiracy theories or media bias, but rather, has long been my commitment to being a civil servant for all of Oregon.”

But Perkins is unlikely to win the November election. The seat has been rated as safely Democratic by Larry Sabato’s Crystal Ball at the University of Virginia’s Center for Politics, and incumbent Democratic senator Jeff Merkley won his last race in 2014 by 19 points.